The most common and most likely answer to this crossword clue is the 6 letter word STITCH
S
T
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T
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H
More clues leading to the result STITCH
- Problem for side having very little to wear?
- Pain in the side, an irritation on the way
- Output from sewer long undermining roadway
- Something surgeon provides for pain
- Small dwarf, a potential pain in the long run?
- Holy person getting with it at church can be a pain
- Stone an irritation? An annoyance when running
- Pain, one produced by needle?
- Idiot in school becoming a pain
- A sharp pain — darn!
Buddy explains!

The straight part
We know that "Pain in the side" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case pain in the side = stitch.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does STITCH mean?
STITCH noun- A single pass of a needle in sewing; the loop or turn of the thread thus made.
- An arrangement of stitches in sewing, or method of stitching in some particular way or style.
- An intense stabbing pain under the lower edge of the ribcage, brought on by exercise.
- A single turn of the thread round a needle in knitting; a link, or loop, of yarn
- An arrangement of stitches in knitting, or method of knitting in some particular way or style.
- A space of work taken up, or gone over, in a single pass of the needle.
- A fastening, as of thread or wire, through the back of a book to connect the pages.
- (by extension) Any space passed over; distance.
- A local sharp pain; an acute pain, like the piercing of a needle.
- A contortion, or twist.
- Any least part of a fabric or dress.
- A furrow.
- The space between two double furrows.
- To form stitches in; especially, to sew in such a manner as to show on the surface a continuous line of stitches.
- To sew, or unite or attach by stitches.
- To practice/practise stitching or needlework.
- To form land into ridges.
- To weld together through a series of connecting or overlapping spot welds.
- (graphics) To combine two or more photographs of the same scene into a single image.
- (more generally) To include, combine, or unite into a single whole.